Effects of Lead on Kinetics of super(3)H Dopamine Uptake by Rat Brain Synaptosomes

Lead inhibits the uptake of tritiated dopamine in synaptosomes of rat brains for both in vivo and in vitro studies. The response is dose related. Dopamine uptake was inhibited at pH 7.5, but in the presence of Pb, uptake of dopamine was inhibited at all pHs tested. In neutral solutions, dopamine uptake in the presence of Pb was most inhibited. Variations in sodium concentration had variable effects on dopamine uptake by rat brain synaptosomes. ATP activation of dopamine uptake was studied under both the influence and lack of Pb. Lead was found to competitively inhibit uptake of tritiated dopamine in rat brain synaptosomes.